Update published 10 September 2020
This investigation (AI-2018-010) examines the Bulla Road Precinct retail centre development at Essendon Fields Airport and how risks associated with the location and height of those buildings were addressed under civil aviation safety legislation and the Airports Act 1996. It also addresses the safety impact of the development on aviation operations at Essendon Airport. These matters arise due to the historical uncertainty in identifying the runway strip width and Obstacle Limitation Surfaces (OLS) for runway 08/26.
The Major Development Plan (MDP) for the Bulla Road Precinct retail centre development was approved by the Minister for Transport and Regional Development in 2004. Building of the precinct was completed in 2005. The MDP located the lower boundary of the transitional surface 90 m from the centreline of runway 08/26 (see Figure 1). That distance was founded on two criteria:
- a runway strip width of 180 m (90 m either side of the runway centreline)
- the location of the lower boundary of the transitional surface immediately adjacent to the runway being determined by the runway strip dimensions.
Using these criteria, the MDP placed the buildings immediately adjacent to and just below the transitional surface associated with runway 08/26. Had they intruded into the transitional surface, an approval would have been required under Part 12 of the Airports Act 1996, and the Civil Aviation Safety Authority (CASA) would have considered the development as being obstacles requiring determination under the relevant safety regulations.
A depiction of the proposed development superimposed onto a Google Earth image of Essendon Airport in 2003. The transitional surface grounded boundary is 90 m from the runway centreline.
Source: Google Earth, modified by ATSB
Runway strip expansion
In November 2015, CASA promulgated CASA instrument 153/15, which was issued to the airport operator. This instrument required the operator to publish the overall strip width for runway 08/26 as 300 m. The basis of this requirement was that there was no record on how the 180 m runway 08/26 strip width had originated, nor were there records as to the previous standard under which that measurement was authorised. The 180 m runway strip width was not authorised under the 2015 version of the standards, which required a 300 m strip width (150 m either side of the runway centreline).
The effect of this mandated 300 m runway strip requirement was to move the associated lower boundary for the transitional surface out to a distance of 150 m from the runway centreline. The change in the strip width also caused a significant portion of the northern most sections of the retail centre buildings to impinge onto the runway 08/26 strip and penetrate that runway’s transitional surface (see Figure 2). In doing so, these portions of the buildings became obstacles on the movement area, and in being obstacles, the buildings were identified as a potential risk to aircraft operations on that runway.
A depiction of the required 300 m runway strip width and the relocated transitional surface, superimposed onto a Google Earth image of Essendon Airport in 2019. The transitional surface grounded boundary is 150 m from the runway centreline.
Source: Google Earth, modified by ATSB
The aerodrome standards provided a means by which CASA could approve obstacles on the movement area. Further, as these obstacles breached the OLS they were required to be illuminated and notified as obstacles through publication in the Aeronautical Information Package (AIP). Instrument 153/15 provided the required authorisation for the presence of the buildings in the movement area and directed the lighting and notification requirements.
In March 2019, the airport operator notified all operators and tenants of Essendon Fields Airport of the intent to return the runway 08/26 runway strip width to the original published 180 m, as it had been from 1972 to 2015. This was done by ‘grandfathering’ the 180 m runway strip width dimension against the requirements of an earlier standard. The notice also stated that the buildings previously approved as obstacles as a result of the application of the CASA instrument would no longer be classified as obstacles with the return of the strip width to 180 m.
CASA accepted that the grandfathering of the runway strip width by Essendon Airport met the requirements of the standards. In May 2019, CASA repealed instrument 153/15. The November 2019 edition of the AIP stated the runway 08/26 strip width as 180 m, and reference to the previously reported obstacles was removed. The effect of the change in the runway strip width was to return the transitional surface to the position as depicted in Figure 1.
In Quarter 4 of 2019, a draft report on the ATSB’s investigation into the Bulla Road Precinct approval was distributed to directly involved parties for comment.
During the review process, the ATSB determined that further evidence was required to consider the effect of the revocation of instrument 153/15. This has necessitated re-engagement with the airport operator, CASA, the Department of Infrastructure, Transport, Regional Development and Communications, and the International Civil Aviation Organization.
Should safety issue/s be identified during the course of this ongoing investigation, relevant parties will be immediately notified so that appropriate safety action can be taken.
An amended draft report is expected to be distributed to directly involved parties in Quarter 4 of 2020.
The information contained in this update is released in accordance with section 25 of the Transport Safety Investigation Act 2003 and is derived from the initial investigation of the occurrence. Readers are cautioned that new evidence will become available as the investigation progresses that will enhance the ATSB's understanding of the accident as outlined in this update. As such, no analysis or findings are included.
On 21 February 2017, a building that is part of the Essendon Airport Bulla Road Precinct retail centre was struck by a Beechcraft King Air B200 (VH-ZCR). The ATSB’s preliminary report for this accident was published in March 2017. This preliminary report stated that the approval process for this building would be a matter for further investigation.
The building was part of the Bulla Road Precinct Retail Outlet Centre development, which was proposed by the lessee of Essendon Airport in 2003 and approved by the Federal Government in 2004.
Due to the specialist nature of the approval process and airspace issues attached to the retail centre development, and not to delay the final report into the accident from February 2017, the ATSB has decided to investigate this matter separately.
The investigation will examine the building approval process from an aviation safety perspective, including any airspace issues associated with the development, to determine the transport safety impact of the development on aviation operations at Essendon Airport.
A final report will be released at the conclusion of the investigation. Should a critical safety issue be identified during the course of the investigation, relevant parties will be immediately notified so that appropriate safety action can be taken.
|Date:||21 February 2017||Investigation status:||Active|
|Investigation level:||Systemic - click for an explanation of investigation levels|
|Location:||Essendon Airport, Bulla Road Precinct Retail Outlet Centre||Investigation phase:||Final report: Approval|
|Release date:||10 September 2020|
|Anticipated completion:||1st Quarter 2021|